Printing plate locking device



March 10,1942. w. F. HUCK 2,275,764

PRINTING PLATE LOCKING DEVICE Filed Oct. 15, 1940 2 Sheets-Sheet 1 March 10, 1942. w, uc 2,275,764

PRINTING PLATE LOCKING DEVICE Filed Oct. 15, 1940 2 Sheets-Sheet 2 "*--*-'""-r i P P L 0) 1 Z 1 I l lume/whom Patented Mar. 10, 1942 PRENTING PIATE LOCKING DEVICE William F. Huck, Richmond Hill, N. Y., assignor to R. Hoe & 00., New York, N. Y., a corporation of NewYork 10 Giaims.

This invention relates to printing plate clamping or locking mechanism, and more particularly to certain improvements in plate clamping clips.

In the plate clamping mechanism heretofore employed, the bodies or blocks of each clamping clip are slidably mounted in grooves or guides formed in the plate or form cylinder. Clamping screws or other members are provided to move the clips to thereby force the beveled edges of their clamping rings into clamping engagement with the beveled edges of the printing plates, to thus secure the plates to the cylinder surface. The clip bodies or blocks slide back and forth in the grooves or guides provided therefor, to and from engagement with the plates, and after a time both the guide portions of the. clip body and the guide portions of the cylinder grooves become worn so that the clip bodies are loosely supported in the cylinder guides. When the beveled clamping rings of the plate clips are forced into clamping engagement with the beveled terminals of the printing plates, the beveled port-ion of the clip ring tends to ride upwardly along the beveled edge of the plate, and the loose fit of the clip body in its guides permits a portion of the clip body which is located immediately adjacent the clip clamping ring to also ride upwardly and carry with it a portion of the printing plate, thereby lifting a portion of the printing plate from the supporting surface of the plate cylinder. When this portion of the printing plate engages the cooperating impression cylinder, it is forced downwardly against the plate cylinder surface, but as soon as the printing plate is moved from engagement with the impression cylinder it again rises from the plate cylinder surface. This repeated movement of the printing plate eventually works it loose from the plate clips so that it may be thrown from the cylinder.

It is an object of this invention to provide a plate clip which is constructed to clamp and maintain the printing plate on the peripheral surface of the printing cylinder, and also support a portion of the plate in this position.

Another object of this invention is to provide plat-e clips employed in printing plate clamping mechanism in which each clip is provided with separate movable components adapted to engage the cylinder guides, and support a portion of the printing plate, and to constantly remain in fixed relation to the cylinder and the supported plate even though a portion of the plate clip should move outwardly or radially during the clamping operation.

A specific object of this invention is -to provide improved plate clips for printing plate clamping mechanism in which each clip body is slidable in a clip slot formed in the plate cylinder, and is provide improved plate clips for printing plate clamping mechanism in which each clip body is slidable in a clip slot formed in the plate cylinder and is cut away so that the cutaway portion is disposed below the peripheral surface of the printing cylinder, and the cut away portion of the clip body is provided with radially movable blocks which interfit with the guide grooves or members of the clip slot to thereby slidably move with the clip body within the clip slot but are supported against'radial movement by the clip slot guides and the cylinder, the blocks being located to support a portion of the printing plate which overlies the clip slot so that relative radial movement of a portion of the clip body does not lift the printing plate from the supporting surface of the printing cylinder.

It is also an object of this invention to provide a plate clip of generally improved construction, whereby the device will be simple, durable and inexpensive in construction, as well as convenient, practicable, serviceable and efiicient in its use.

With the foregoing and other objects in view, which will appear as the description proceeds, the invention resides in the combination and arrangement of parts, and in the details of construction hereinafter described and claimed, it being understood that various changes in form, proportion, and minor details of construction may be made Within the scope of the claims without departing from the spirit or sacrificing any advantages of the invention.

For a complete disclosure of the invention, a detailed description of it will now be given in connection with the accompanying drawings forming a part of the sepcification, wherein:

Figure 1 is a fragmental longitudinal sectional view taken through the conventional plate or form cylinder of a printing machine and depicting the improved plate clips in operable association therewith;

Figure 2 is a fragmental end view of the printing cylinder showing the improved clamping clips applied thereto;

Figure 3 is a transverse sectional view taken through an end clip on the line 33 of Figure 1;

Figure 4 is a transverse sectional view taken through an end clip and supporting blocks on the line 44 of Figure 1;

Figure 5 is a longitudinal sectional view taken through the end clip with cooperating parts broken away;

Figure 6 is a plan view of the end clip;

Figure 7 is a longitudinal sectional view taken through an intermediate clip, cooperating parts being omitted; and

Figure 8 is a plan view of the intermediate clip.

Referring to the drawings, in which similar reference characters designate corresponding parts, there is depicted a conventional plate or form cylinder I0, of a rotary printing press, having a central clip ring secured thereto, and provided with overhanging arcuate beveled edges I2 to engage the arcuate beveled edges I3 of inner printing plates I5, bestseen in Figure 1. Inasmuch as the plate-supporting portion of both terminals of the plate or form cylinder II) are similar, only one end of the cylinder is depicted in these drawings.

The outer arcuate beveled edge I3 of the inner printing plate I5 is engaged by an overhanging arcuate beveled edge l5 of a clamping ring I! of an intermediate plate clip I8. Usually in plate clamping clips employed for securing printing plates on the supporting surface of the plate cylinder of a newspaper printing press, three or more sliding bodies or blocks are secured to a single clamping ring which extends partly around the cylinder surface and engages the arcuate beveled edge of the printing plate. In other structures, however, a single sliding block or body may be employed for each clamping ring, and it is to be understood that this invention is directed to plate securing clips of either type.

Each body portion 20 of the intermediate clip I8 is slidably received in a longitudinally-extending clip slot 2| which is formed in the peripheral portion of the plate cylinder Ill.

Outer plate clips I9 are provided, and the body portion 22 of each outer plate clip structure I9 is mounted for longitudinal sliding movement in a clip slot 2|, and this clip body 22 supports a clip or clamping ring 23, or a portion thereof, having an arcuate beveled edge 25 which engages the outer beveled edge 26 of an outer printing plate 21, the inner beveled edge 26 of the plate 27 being engaged by the outer beveled edge l6 of the clamping ring I! of the intermediate clip l8.

In clip structures where three sliding bodies or blocks are employed to support a common clamping ring, the intermediate block usually cooperates with locking or clamping instrumentalities, and in the present arrangement each locking body or block 22 of the outer clip I9 is provided with a longitudinally or axially extending threaded aperture 30 which operably receives the threaded stem 3| of a clamp screw 32 that is swiveled to the cylinder I0 by plates or segments 33 and 34. Each segmental plate 34 has a cylindrical recess 35 formed therein to rotatably receive a collar 35 formed on the screws 32.

Each screw 32 is provided with a tool-engaging portion 37, so that it may be conveniently rotated, and when the screw is rotated, the beveled edge 25 of the clamp ring 23 of the outer plate clip I9 is forced against the outer beveled edge 26 of the outer plate 21. This, in turn, forces the plate 2! inwardly until the outer beveled edge I6 of the clamping ring ll of the intermediate clip I8 is engaged by the inner beveled edge 26 of the outer plate 21. Now the inner beveled edge I6 of the clamping ring ll of the intermediate clip also engages the outer beveled edge |3 of the inner'plate I5, which, in turn, forces the inner beveled edge I3 of the inner plate against the beveled edge I2 of the central clip ring thereby securing the inner plate I5 and the outer plate 2'! to the peripheral surface of the printing cylinder IE1. However, if the outer plate 21 is not employed, then the inner terminal of a body 22 of the outer plate clip engages a collar or head 40 carried at the outer terminal of a binder rod 4| which is mounted for longitudinal sliding movement in a filling block 42 positioned in the intermediate portion of the clip slot 2|. Continued inner movement of the clip body 22 forces the binder rod 4| against the outer terminal of the intermediate clip body 20, thereby'clamping the inner plate I5 on the supporting surface of the plate cylinder II).

The foregoing structure and its operation conforms to the conventional practice, which is well understood by those skilled in the art. Such construction has proven unsatisfactory however, because after a time the portion of each clip slot which operably engages a sliding clip body becomes worn, and portions of the clip body also become worn, thereby resulting in considerable radial play between the clip slot guides and the clip body. When the clip screw 32 forces the beveled surface of a clip ring to engagement with the beveled terminal of a printing plate, the clip ring tends to ride upwardly along the beveled surface of the printing plate and carriesa portion of each plate clip body upwardly with it, thereby lifting a portion of the printing plate away from the supporting surface of the plate cylinder. In this condition, when the printing plate engages the cooperating impression cylinder it is forced back to the supporting surface of the plate cylinder until it again disengages the impression cylinder. This continued radial movement of the plate relative to the plate cylinder-causes the plate to become loosened from the plate clip rings and to finally be thrown from the plate cylinder.

Applicant, in order to avoid this objection, has constructed each clip so that the printing plate is rigidly supported on the peripheral surface of the plate cylinder even though a portion of the plate clip should be deflected outwardly or radially during the clamping operation. While any preferred guide instrumentalities may be employed for guiding each plate clip in the clip slot 2| of the plate cylinder In, it is preferred that the portion of the clip slot 2| which engages each clip be provided with, as best seen in Figures 3 and 4, opposed inwardly extending rails 45 which define opposed outwardly extending rectangular grooves 46 in the lower portion of each clip slot 2|, and opposed outwardly extending tapered or beveled grooves 47 formed in the upper portion of each clip slot 2|. The body of each plate clip is slidably received within a clip slot 2|, and each body is provided with opposed outwardly extending rectangular ribs 48 which are slidably received within the rectangular grooves 46, and opposed outwardly extending tapered or beveled ribs 49 which are slidably received within the tapered or beveled grooves 41.

By this arrangement, the body of each clip is slidably received within the clip slot 2|, but is held against radial movement by the engagement of the ribs 48 and 49 with the walls of the grooves 45 and 47.

The body 22 of each end clip is provided with opposed radially-disposed rectangular recesses 50, which receive therein for radial sliding movement opposed supporting block-s 5|. Each block 5| is provided with an outwardly extending rectangular rib 52 and an outwardly extending beveled or tapered rib 53, the ribs 52 and 53 corresponding to the ribs 48 and 49 of the clip body 22, and they are slidably received within the recesses 45 and 41 of the clip slots 2|. The portion of the end clip body 22 in which the blocks 5| are received has its outer surface cut away or under cut, as indicated at 55, to provide an inset surface 55 which is located below the periphery of the plate or form cylinder It, as best seen in Figures 3, 4, 5, and 6. The blocks 5|, however, extend above the inset surface 56 of the clip body and engage the inner face of the printing plate, as best seen in Figure 4, to thereby bridge a portion of the clip slot 2| and support the printing plate out of engagement with the inset surface 56 of the clip body, for a purpose to be hereinafter disclosed.

Each intermediate clip body 22 is similar in construction to the end clip body 22, except that it 'is elongated, and its clamping ring I1 is positioned centrally thereof. The body 25 of each intermediate clip I8 is provided with two sets of the opposed rectangular slots 50 which receive for lateral sliding movement therein the blocks 5|. The body 26 of each intermediate clip I8 has its outer surface cut away or under cut, as indicated at 55, to provide inset surfaces 56 similar to those provided in the end clip bodies.

After the inner and outer plates l5 and 2! have been securely clamped, in the manner described, on the surface of the supporting plate cylinder H], a portion of each plate which overlies the clip slots 2| is supported by the outer arcuate surface 65 of each block 5|, so that the plate does not engage the inset surface 56 of the clip body. After continued use of the guide surfaces of the clip body and the clip slots, these surfaces become worn, thereby permitting the portion of the clip body which is located immediately adjacent the clamping ring of each clip to move outwardly. Ordinarily, as hereinbefcre stated, the outward movement of this portion of the clip body carries the adjacent portion of the printing plate outwardly with it, thus lifting it from the supporting surface of the printing cylinder H).

In applicants improved clamp, however, the under cut portion or portions of each clip body may yield outwardly an appreciable distance without its inset surface or surfaces 56 engaging the supported plate, and at the same time the plate is securely supported by the blocks 50, thus enabling the printing plates to remain securely clamped to the supporting surface of the plate cylinder l0 even though the sliding surfaces of the clip body and clip slot may have become worn sufficiently to permit appreciable outward radial movement of a portion of the clip body relative to the plate cylinder.

It will be understood that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, and it will be slide in a groove, a clip ring carried by the bodyand adapted to urge a plate in a direction towards the body, and separate plate-supporting blocks carried by the body and slidable therewith and movable relative to the body along said direction, the height of each block being greater than the thickness of the adjacent portion of the body.

2. As an article of manufacture, a printing plate locking clip, including a body adapted to slide in a groove, a clip ring carried by the body and adapted to urge a plate in a direction towards the body, and separate plate-supporting blocks carried by the body and slidable therewith and movable relative to the body along said direction, the top of each block extending above the top surface of the adjacent portion of the body.

As an article of manufacture, a printing plate locking clip, including a body adapted to slide in a groove and having recesses formed therein, a clip ring carried by the body and adapted to urge a plate in a direction towards the body, and a plate-supporting block supported in each recess for sliding movement along said direction, the top of each block extending above the top surface of the adjacent portion of the body.

4. As an article of manufacture, a printing plate locking clip, including a body adapted to slide in a groove and having recesses formed in i the opposed longitudinal edges thereof, a clip ring carried by the body and adapted to urge a plate in a direction towards the body, guide members formed along the'longitudinal edges of the body, plate-supporting blocks received for sliding movement along said direction Within the recesses, the top of each block extending above the adjacent top surface of the body, and guide members extending along the outer edge of each block.

5. As an article of manufacture, a printing plate locking clip, including a body having a recess extending from top to bottom through each longitudinal edge thereof, a clip ring carried by the body, the top portion of the body which is adjacent the clip ring and which surrounds the said recesses being cut away so that it extends below the top of the body, a plate-supporting block mounted for sliding movement within each recess along directions toward the top or bottom of the body, the top of each plate-supporting block extending above the cut away portion of the body.

6. In a printing plate locking device, the combination with a plate cylinder having longitudinally-extending clip slots formed therein, of an intermediate plate locking clip having a body slidably mounted within a clip slot, a beveled clip ring supported at the central portion of the intermediate clip body and adapted to urge a plate in a direction towards the body, plate-supporting blocks carried by the body and slidab-le therewith and movable relative to the body of the intermediate clip along said direction and located at opposed sides of the clip ring, an end plate locking clip having a body slidable within a clip slot, a beveled clip ring supported at the outer terminal of the end clip body and adapted to urge a plate in a direction towards the body, plate-supporting blocks carried by the body and slidable therewith and movable relative to the end clip body along said direction, the blocks being located adjacent the clip ring and the height of each block being greater than the thickness of the adjacent portion of the clip body to thereby support portions of the plate which overlie the clip slot.

7. In a printing plate locking device, the combination with a plate cylinderhaving a longitudinally-extending clip slot formed in the peripheral portion thereof, of a body adapted to slide within the clip slot, a beveled clip ring carried by the body and adapted to urge a plate in a direction towards the body, separate plate-supporting blocks carried by the body and slidable therewith and movable relative to the body along said direction and the height of each block being greater than the thickness of the adjacent portion of the body to thereby support a portion of the plate which overlies the clip slot.

8. In a printing plate locking device, the combination with a plate cylinder having a longitudinally-extending clip slot formed in the peripheral portion thereof, of a body slidable within the clip slot, the body having recesses formed therein, a beveled clip ring carried by the body and adapted to urge a plate in a direction towards the body, a plate-supporting block slidably supported within each recess along said direction and the height of each block being greater than the thickness of the adjacent portion of the body to thereby support a portion of the plate which overlies the clip slot.

9. In a printing plate locking device, the combination with a plate cylinder having a longitudinally-extending clip slot formed in the peripheral portion thereof, guide members located within the clip slot, of a body slidable within the clip slot and having recesses formed in the opposed longitudinal edges thereof, a beveled clip ring carried by the body and adapted to urge a plate in a direction towards the body, guide members formed along the longitudinal edges of the body for sliding engagement with the guide members of the clip slot, plate-supporting blocks received for sliding movement relative to the body along said direction within the said recesses, the top of each block extending above the adjacent top surface of the body to support a portion of the plate which overlies the clip slot, guide members extending along the outer edge of each block for sliding engagement with the clip slot guide'members.

10. In a printing plate locking device, the combination with a plate cylinder having a longitudinally-extending clip slot formed in the peripheral portion thereof, of a body slidable within the clip slot and having a rectangular recess extending from top to bottom through each longitudinal edge thereof, a beveled clip ring carried by the body and adapted to urge a plate in a direction towards the body, the top portion of the body which is adjacent the clip ring and which surrounds the said recesses being cut away so that it extends below the top of the body, a platesupporting block mounted for sliding movementrelative to the body along said direction in each recess, the top of each plate-supporting block extending above the cut away portion of the body to support a portion of the plate which overlies the clip slot.

WILLIAM F. HUCK. 

